This invention is related generally to wireless communications and, more particularly to a system and method of incorporating the line-selection and direct station selection (DSS) functions, associated with land-line telephones into wireless communication systems such as cellular telephone and personal communication systems (PCS).
The use of line-selection buttons is well known with traditional land-line services, especially in a business environment. A business office of many phones, for example, ten phones, may only have access to a smaller number of outside lines, for example, three lines. Each phone is then equipped with at least three special keys that allow a telephone user to capture, or select an outside line.
Each telephone is also equipped with the set of lights it, corresponding to each line selection key. These lights, or indicators are called a busy lamp field (BLF). The BLF indicators signal the availability of corresponding outside lines. The BLF indicators of participating phones signal users that a line has been captured, when one of the group phones is using that particular line.
The phones may also be equipped with DSS buttons. Then, each phone or station corresponds to a particular DSS button. The user of one phone can directly access another phone in the system by simply pushing a DSS button. This DSS function may exist even though the phones all have unique telephone numbers.
Associated with each DSS button is a busy lamp field indicator. The BLF lamp signals to each phone in the system, the status of each participating phone. The lighting of the BLF lamp lights is patterned to signal different statuses. One particular pattern may signal that a phone is being used. Other signal patterns indicate when the phone is idle, on hold, or ringing.
Many cellular system are also limited in the number trunk lines available in the system between base stations and mobile switching centers (MSCs), or between MSCs and the land-line telephone network. However, the real bottle-neck is in the number of wireless channels available. Crowding of wireless channels is especially prevalent during certain times of the day. Little has been done to warn a user of a high system load, and likelihood of being able to complete a call, before the call is attempted. Little has been done to insure a higher probability of making and completing a call for users willing to pay an extra premium.
It would be advantageous if a wireless communications system could be organized to provide a DSS function between a selected group, or sub-group of mobile stations.
It would be advantageous if a wireless communications system could be established in a local system interfaced to existing telephone land-lines and providing a land-line selection capability.
It would be advantageous if users of a group-distributed, or public communications system had the capability of reserving wireless communication channels. Further, it would be advantageous if the users had virtual DSS capability. When interfaced with a private wireless system, it would be advantageous if a user had line selection privileges in the private system when operating in either the private or public systems,
Accordingly, a system including transceiving mobile stations with direct station selection (DSS) and line-select modes of operation is provided. One communications system includes at least one dedicated transceiving base station interfaced to a first subset of telephone circuits to form a private wireless network. Each mobile station comprises a set of keys, which when activated, operate in the line-selection and DSS mode. A first subset of keys are line-select keys, and a second subset of keys are DSS keys. Each of the first subset of line-select keys corresponds to a telephone circuit, typically the telephone circuit is an analog or digital land-line including time division multiplex (TDM) and integrated services digital network (ISDN). In some aspects of the invention, the dedicated base station is interfaced to the main land-line system through wireless channels. It is transparent to the user whether these telephone circuits are themselves land-lines, or are wireless. The telephone circuit is selected in response to activating a corresponding line-select key.
Each of the second subset of DSS keys corresponds to a like-numbered subset of mobile stations directly accessed by activating the DSS keys. In this manner, a dedicated land-line or station is selected with a single key stroke.
Typically, the mobile station includes a busy lamp field (BLF). The BLF is made up of line-select signal indicators whose number is equal to the number of keys in the first subset of line-select keys, plus the number of keys in the second subset of DSS keys. Each one of the line-select indicators corresponds to one of the line-select keys, and each one of the DSS indicators corresponds to one of the DSS keys. The line-select indicator signals the availability of the corresponding telephone circuit, and the DSS indicator signals the availability of its corresponding station. The DSS functions indicate whether another phone in the system is idle, busy, on hold, ringing, or turned off. Each function is associated with a unique BLF indicator signal.
In some aspects of the invention, the keys operate in a second, telephone keypad mode. The keys are each identified with corresponding telephone keypad alphanumeric characters, and are used to manually dial a telephone number. The dual-function keys permit the phone to operate in the traditional dialing mode. A mode switch selects between the line-select/DSS mode, and the keypad mode of operation.
The mode switch can be activated by the mobile station, or by a communicating base station. The mode switch can literally be a switch manually operated by the phone user. Alternately, the mobile station has a logic system with a predetermined set of conditions required to activate the mode switch. When the conditions are met, the mobile station automatically activates the mode switch to operate in the second, telephone keypad mode of operation, from the first mode, or vice versa.
The mode switch can also be enabled with the use of a keypad cover. Typically, the closing of the cover would switch the phone from the first to the second mode of operation. Since the cover conceals the BLF, there is no need to operate the BLF. Minimizing the use of the BLF saves battery power. Alternately, the cover disables the BLF without switching out of the first, line-select/DSS mode. Likewise, the cover can be used to automatically trigger the mode switch to engage the first, line-select/DSS mode when the cover is opened.
Ideally, the BLF indicators and alphanumeric characters are integral to said corresponding keys. This makes the correspondence between a key and its function very clear. The BLF indicators can be lights, such as LEDs. Alternately, the integral BLF indicators are light arrays, such as LCDs. Further, the keys could be virtual keys on one large LCD screen equipped with sensors to determine if the virtual keys have been activated.
In some aspects of the invention, the line-select/DSS functions are available for use with a group-distributed, or public wireless network, where the stations maintain long-range monitoring of line-select/DSS functions using group-distributed system base stations as a relay. This arrangement would allow a phone in the private system to monitor a DSS mobile when it was far from the dedicated local system base station. Further, the DSS mobile registered in the public system can use the line-select function so that its calls are monitored and billed as if the mobile was registered in the private system. Alternately, at least a DSS mode can be established between a select group of mobile stations through just the use of a group-distributed system of base stations, and a modification of existing protocols. That is, one DSS capable mobile phone can be used to monitor the status of a select group of phones operating in a large network of hundreds of base stations and thousands of mobile stations.
To insure communication links between mobile stations in crowded group-distributed systems, the present invention permits special users priority use of wireless channels interfacing participating mobile stations and public system base stations. These special user mobiles access the reserved wireless channels through the line-select (now called a channel-select) function of the mobile phone. BLF indicators signal the availability of priority channels. The DSS and keypad modes of operation can also be added to the channel-select system.
A method of operating mobile stations in the line-select/DSS modes of operation is also provided. The line-select mode operates as follows:
1) establishing a first subset of keys having the lines selection function, with each line-select key corresponding to a telephone circuit;
2) activating a line-select key corresponding to an available telephone circuit; and
3) in response to activating the line-select key, capturing the telephone circuit for use by the mobile station.
The DSS mode operates as follows:
1) establishing a second subset of keys having the DSS function, with each DSS key corresponding to one of the stations;
2) activating a DSS key; and
3) in response to activating the DSS, accessing the corresponding station, whereby the mobile station is able to select land-lines and directly link to a predefined group of stations.
A subset of busy lamp field (BLF) indicators are provided, including a first subset of line-select indicators, with each line-select indicator corresponding to one of the telephone circuits, and a second subset of DSS indicators, with each DSS indicator corresponding to a station. The method includes steps to establish a correspondence between the line-select indicators and the line-select keys. Then, the line-select indicators are used to signal the availability of the telephone circuits. The line-select key is activated in response to the line-select indicator signal. Likewise, steps are included to establish a correspondence between the DSS indicators and the DSS keys. The DSS indicators signal the status of the stations, and the DSS key is activated in response to the DSS indicator signal.
As in a traditional phone, alphanumeric indicators are provided, and the mobile stations incorporate a second, telephone keypad mode of operation. The method comprising the additional steps of:
disabling the first, line-select/DSS mode of key operation, and enabling the second, telephone keypad mode;
establishing a correspondence between the alphanumeric indicators and the keys; and
activating the keys to manually dial a telephone number.